PURPOSE: To simplify the mechanism, facilitate the manufacture and reduce the cost by equipping a valve main body separately with a safety valve releasing abnormal pressure on a circuit and a suction valve preventing negative pressure.

CONSTITUTION: A valve main body 30 is provided with a shiftable spool 31 and a return spring 32 holding the spool 31 in a neutral position, while a safety valve 33 and a suction valve 34 are separately installed between a cylinder port 30e and a cylinder drain port 30f. A load check valve 35, allowing a passage only to a bridge port 30d side, is installed between a parallel port 30c and the bridge port 30d, while the bottom side and rod side of a hydraulic cylinder 36 are connected to a cylinder port 30e through a passage 37. The mechanism of valve is simplified, and the valve is easily manufactured at a low cost while being miniaturized.